Agronomical practices to reduce the risk of Rosy apple aphid (Dysaphis plantaginea) occurrence in organic fruit production (Biofruitnet Practice Abstract)

Summary

Better growth of the tree and nutrients availability, resilience against other aphids and diseases, production of marketable fruits and higher profitability of the organic farm.
Practical recommendations
To include in the overall orchard management system:
• Fertilisation: Apply organic N fertilisers based on soil and leaves analysis, nutritional needs of the trees and expected rate of mineralisation of the organic fertiliser (OF). Use leguminous cover crops to stabilise nitrogen availability and reduce the need of OF. If applying different OFs, split the dose in two stages (i.e., first application before flowering, and the second after flowering).
• Irrigation: Base irrigations regime on the soil water measures using sensors or models to keep the optimum soil moisture (between field capacity and allowable depletion).
• Pruning: Ensure proper crown development, reduce the presence of dense areas (they received little light and air circulation). Prune root suckers which grow out of the rootstock.
• Control Plantago lanceolata (secondary host) with cover cropping, weed control methods, etc.
• If infestation is high, remove the infested shoots and destroy them outside the orchard.
• Establish hedgerows or flower strips to favour natural predators (e.g., coccinellids, green lacewings, syrphid flies, etc.) or parasites (e.g., Hymenoptera) and reduce the population in the late spring-summer.